MOISTURE PERMEABLE WATERPROOF FABRIC AND MANUFACTURING METHOD THEREOF

Abstract: Moisture permeable waterproof fabric and manufacturing method thereof which is excellent in moisture permeability and very much soft in touch feeling. The moisture permeable waterproof fabric manufactured by conventional wet and dry types was insufficient in moisture permeability and waterproof property and was hard in touch feeling. And the wet type manufacturing method produced much waste water and productivity was low. This invention is a moisture permeable waterproof fabric in which polyurethane beads are cross-linked instead of moisture permeable waterproof fabric made in honeycomb shape in gaps and minute gaps are formed among said urethane beads. The invention is a method for manufacturing moisture permeable waterproof fabric in which polyurethane emulsion composition made of polyurethane resin, solvent, water, linking agent and emulsifying agent is applied to base fabric, and then firstly the solvent is removed and thereafter the polyurethane beads are made to be coagulated, and secondly water is evaporated so that gaps are formed. The invention can be utilized for raw fabric for various kinds of sports wear.

Description: MOISTURE PERMEABLE WATERPROOF FABRIC AN!) MANUFACTURING METHOD THEREOF DESCBUeilQN IEGHHXCΔ JEIELI1 This invention relates to a moisture permeable waterproof fabric and manufacturing method thereof in which minute polyurethane beads are layered on surface of base fabric at a crosslinked state and a multiplicity of fine gaps are formed among the crosslinked minute polyurethane beads. BACKGBQUHD_ABI Conventional moisture permeable waterproof fabric has disadvantage that at first it is made by laminating a fluorine resin film with woven and/or knitted fabric. and it is very excellent in moisture permeable waterproof property but on the contrary it is expensive. Secondly, there is one which is coated with polyurethane on surface of woven and/or knitted fabric, and this is generally classified to porous film type and non-porous type. And, the porosity coating method is generally classified to a dry type method and wet type method, and among these, the dry type method is a method for coating an acryl resin solution by a dry type, and which has shortcomings that the waterproof property (water pressure resistance : 500 - 1000 mmH*2θ) and moisture permeability (less than 3500 g/m 2 .24H> are inferior and touch feeling is hard, and since the wet type method produces much waste water and it should coagulate for a predetermined time period, productivity iε inferior. At the same time, aforesaid wet type method has problem that the touch feeling becomes hard because it has to make thickness of film layer to be thicker to about 50 - 70 urn in order to give the water pressure resistance. And, since a non-porous film type has a mechanism emitting to exterior after absorbing a moisture emitted from a human body and thereby be swollen and d mped, it has problem that concave and convex are produced to film and making its external appearance to be hurt because of uneven swelling and damping phenomenon in a swelling and damping process by moisture. DISCLOSURE OF. INVENTION The present invention is that which soJved the problems of conventional moisture permeable waterproof fabric and manufacturing method thereof as described above, and it is an ob.iect of the present invention to provide a moisture permeable waterproof fabric and manufacturing method thereof which iε very much excellent in waterproof property and moisture permeability and tender in touch feeling. Feature of the present. invention resides in moisture permeable waterproof fabric and manufacturing method thereof in which minute polyurethane beads have a multiplicity of fine gaps and simultaneously layered as they are crosslinked. RRIEEJOESCBIEIIPH QF DBAftlN&S FIG.1 is a diagram showing that micro-geJ exists in a colloid suspension state, FIG.2 is a diagram showing a state before drying in this invention, FIG.3( ) is a diagram showing a state at a time of firstly drying in this invention, FIG.3(B) is a diagram of a state after first drying in this invention. FIG.4(A) is a diagram of a state at s time of secondly drying in this invention, FIG. (B) iε a diagram of a state after second drying in this invention. Hereinafter, a preferred embodiment of the present invention will be described more in detail with reference to the accompanying drawings. Base fabric (e.g. : 210T nylon fabric) having sufficient density are calendared whereby their surface state are made to be smooth and then water repelling processed by a fluoro-resin type water repellent agent (e.g. : Scotch Guard). Successively, coating emulsion was prepared as follows. 65 part to 45 part in weight ratio of polyurethane resin (UE1000-N; product of Dainichi Seika, Japan) was dissolved to diluting solution. Solvent mixed with toluene and M.E.K . (Methyl Ethyl Ketone) was used as a diluting εolution , and added quantity was 23 part to 10 part in weight ratio. The mixing ratio of aforesaid two organic solvent was made to be equal . To said solution, linking agent (Rezamin-X ; product of Dainichi Seika, Japan is added at 30 part to 0.1 part in weight ratio, emuisifier (Resamin UP 31 ; product of Dainichi Seika, Japan) at 4.5 part, and Dicrylan Catalyst Ξ.L.-MP ; Ciba geigy, Germany) at .1.0 part. Next, to said mixed solution, 30 part in weight, ratio of pure water was added and then mixed with stirring for more than twenty(20) minutes. In accordance with the urethane emulsion composition prepared as described above, as shown in FIG.l, micro-gel made of polyurethane, solvent and linking agent was dispersed in a colloid suspension state in water, and surface of the micro-gel became surrounded by emuisifier. In applying the urethane emulsion composition to the base fabric, method such aε ordinary knife coating, overall coating and spray or dot coating can be employed, but the over roll coating system waε employed in this invention. Since the urethane emulsion composition applied to the base fabric exists in a suspension state as shown in FI .2, in order to make only the urethane beadε; to be remained, solvent (toluene and MEK) and non-solvent (water) should be removed through two steps. Firstly, in order to remove the solvent, base fabrir- applied with urethane emulsion composition was stayed for 1 0 c 10 minutes in hot air oven at 60 C - 80 . Applied layer completed with primary drying is coagulated to a polyurethane beads state by water being a non-solvent when the solvent iε all removed as shown in FIG.3(B). At this moment, the part contacted among particles became crosslinked by influence of the linking agent, at a state that coagulation could not be done. Diameter of urethane beads formed in this invention is approximately about 0.1 - 1.5 um. Successively, when it is stayed within a hot air oven *0 0 of 120 C - 150 C for 1 - 10 minutes, the water being a non-solvent became completely evaporated and removed, and spatial portion which had been occupied by water became remained as gaps. {FIG. (B)} In accordance with the moisture permeable waterproof fabric of the present invention, as shown in FIG.4(B), the urethane beads of lowermost layer crosslink the urethane beads of their upper layers as they are adhered to the base fabric, and since innumerably many minute gaps are formed among the minute urethane beads, the moisture permeability and waterproof property are very much excellent than the moisture permeable waterproof fabric made of conventional honeycomb shape. Simultaneously, since the present invention is excellent in moisture permeable waterproof property. thickness of applied layer can be made. τ,o be thinner (20 - 30 um), and since the polyurethane resin exists in a state that the urethane beads are adhered only to surface of the base fabric without being the polyurethane resin iε penetrated into the base fabric as conventional moisture permeable waterproof fabric, the touch feeling is very soft and tender relative to the conventional one. Embodiment 1 After a water repelling process by an aqueous solution of 1 % of fluoro resin type water repellent agent (Scotch Guard, product of 3M co.), dried by using an over roll coater to one surface of nylon fabric and is coated so that thickness of applied layer after drying became to be about 30 jum. At this moment, the urethane emulsion composition was a polyurethane composition emulsified by 54.8 part of UE1000N (polyurethane solid 25%, Dainichi Seika, Japan), 13.7 part of mixed solution mixed with M.E.K and toluene at 1 : 3 as solvent, 0.9 part, of linking agent. 0.9 part of emulsifying agent, and 29 7 par of non-solvent mixed with water and M.E.K And, the solvent was removed by a drying condition of hot. air o + 60 " C 80 " C for five(5) minutes, and again the non- solvent, was removed by hot 3ir of 1 0 C 150 0 i <<t 1i' minutes, (the part in weight, part) _. After a water repelling process by an aqueous solution of 2% of fluoro-resin repellent agent (Scotch Guard, product of 3M co. ) , fabric surface was smoothly made by calendaring one surface of nylon fabric 210 T(density), applied by a condition of embodiment 1 and then processed by adhesive agent by 80 mesh of a gravure coater and thereafter Dobby cloth waε adhered and aged for 24 hours and then a base fabric (nylon) cloth was removed. 5 C_Qrop_arjjQg._ex3JaP-lgL.J_ 70 D nylon fabric (density ; 120 x 90 yarns/inch) was dipped to 2% solution of fluoro-resin type water 0 l repellent. agent and heat treated at 170 C and the adhesive agent. composition of table 1 was applied tn fabric surface and dried and then the polyurethane composition of table 2 was coated by using over rol • coater for the minute gap formation and coagulated and washed and dried and thereafter water repel1inp processed . Table 1. Adhesive agent composition Polyurethane resin 44 weight % Urethane type adhesive agent 20 weight % Organic solvent 32 weight % Silica gel 3.0 weight % Hardening agent 1.0 weight % 1 n Table 2. Polyurethane resin composition 15 Polyurethane resin 73 weight % Organic solvent (Dimethylformamid;DMF) 22 weight % Surface active agent (non-ion) 1 weight % Surface active agent (anion) 1 weight % Pigment 3.0 weight % T* Table 3. Result compared with embodiments and comparing example is same as table 3. Item Embodiment Compared 1 2 example 1 Moisture permeability 11,00 9,000 4,500 JIS Z 0208 (g/m 2 .day) Water pressure resistance 2,000 2,000 1,500 JIS L 1092 (mm HzO) Structure beads layers honeycomb External appearance of resin white white layer Productivity high low Touch feeling very soft hard Processing method dry type wet type

Claims: CLAIMS : 1. Moisture permeable waterproof fabric which is characterized in that polyurethane beads are adhered to surface of base fabric and crosslinked polyurethane beads are layered and connected to upper layer portion thereof, and innumerable minute gaps are formed among said polyurethane beads. 2. Moisture permeable waterproof fabric as defined in claim 1, which is characterized in that diameter of polyurethane bead is 0.1 - 15 um. 3. Method for manuf cturing moisture permeable waterproof fabric which is characterized in that following composition of polyurethane emulsion iε applied to one surface of base fabric and then firstly dried by hot air of 60°C - 80°C for 1 - 10 minutes and thereafter secondly dried by hot air of 130 C - 150 C for 1 - 10 minutes . composition Polyurethane resin : 65 - 45 part Toluene + M.E.K. : 10 - 23 part (toluene : M.E.K. = 1 : 1) Linking agent : 0.1 - 10 part Emulsifying agent : 4.5 part Catalyst : 1.0 part. Water : 30 part (part is weight part) 4 . Method for manufacturing moisture permeable waterproof fabric as defined in claim 3, which is characterized in that adhesive agent is applied on surface of polyurethane bead layer formed after the second drying and then other base fabric is adhered and first base fabric is exfoliated.

Inventors: KIM IN HEE, PARK YOUN HEUM, KIM, IN, HEE, PARK, YOUN, HEUM
Applicants: KIM IN HEE, PARK YOUN HEUM, SUNG WON IND CO LTD, KIM, IN, HEE, PARK, YOUN, HEUM, SUNG WON IND. CO., LTD.
Application year: 1994
Main classification: D06M15
IPC codes: A41D31, D06M15, D06M17, D06M23, D06N3